YouTube member dinthisane shares his first DIY video, and it's pretty clever. Using some ready made inexpensive 'Skate Buds' available online, he was able to create a very effective rotating video dolly. All you'll need is a flat base plate and a Tripod Head or Fluid head. It's a very simple way to go about mounting wheels without creating axles. As you can see these things are designed to carry a bit of weight too. You can find these little Skate Buds below.
For a cheap sturdy head, you can should check out the one that we used on the Korean Clone of the SpiderTrax dolly found here: http://cheesycam.com/test-drive-spidertrax-clone-korean-dolly/